Draft gear



Patented Oct. 18, 1932 DONALD F. SPROUL, OF CHICAGO, ILLINOIS,ASSIGNORTO CARDWELL WESTINGHOUSE COMPANY, A CORPORATION OF DELAWAREDRAFT GEAR Application filed October 30, 1929.

The invention relates to friction draft gears and is herein disclosed inconnection with the Cardwell type of gear.

The improvement is in the form of the guide ribs carried by a movableelement of the gear and engaging longitudinal channels in the gearcasings or chambered followers, the object of the invention being tosecure freedom of movement of the parts under all conditions of service.

The invention consists in draft gear having a movable elementcooperating with chambered followers and provided with guide ribsslidable within longitudinal channels in the follower walls, the sidewalls of the portions of the rib being bowed.

In the accompanying drawing Fig. 1 is a detail plan section of a portionof the framing of a railway car, and of the draft gear embodying theinvention; and

Fig. 2 is a sectional view on the line 22 of Fig. 1.

Portions of a pair of center or draft sills of a railway car are shownat 10, 11 and are equipped as usual with draft and bufiing lugs, onepair of which is shown 12, 13.

The gear adopted for the disclosure of the present invention is oftheCardwell type and comprises a pair of chambered followers 14, 15; a setof wedging and friction developing elements housed within the followers,and spring m ans for resisting the compression of the gear. The wedgingand friction elements as shown comprise two pairs of triangular weclgeblocks 16, 1? and 18, 19 seated respectively against the end walls ofthe followers 14, 15; a central wedging element 20 having its endsinterposed between and cooperating with the triangular blocks of eachpair; and a pair of side wedging elements 21, 22 each engageable withthe outer faces of one of the triangular blocks of each pair.

The resilient means for resisting the compression of the gear comprisesa pair of helical springs 23, 2% mounted upon the ends of a tension bolt25 extending transversely through the set of wedging elements, and thesills, the springs reacting between the outer seats, as 26, fixed uponthe ends of the rod and sliding seats as 27 mounted upon Serial N 0.403,418.

the rod between the inner ends of the springs and the adjacent sideelements 21, 22.

The central wedging element 20 is, as usual, provided with top andbottom guide ribs 28, 29 which slide within longitudinal channels 30, 31formed respectively in the top and bottom walls of the followers 14, 15.

Heretofore, it has been the practice to make such guide ribs of uniformwidth, their side walls being parallel. The relative size of the ribsand the channels has been such as to provide for a free slidingmovement. In practice, distortion of the gear frequently occurs.Theoretically, the transverse faces of the two followers are normal tothe axis of the gear and the longitudinal movement of the various partsof the gear is parallel with such axis. In practice, however, tilting ofthe followers and oblique longitudinal travel of the various elements ofthe gear freelement 20 is not perpendicular to the end walls of both ofthe followers, the straight guide rib binds within the channels,preventing free movement of the gear elements and increasing thedistortion of the gear. In the present invention, the side walls of theend portions 32, 33 are longitudinally bowed, as shown at 34;, 35,permitting the tilting of the element 20 relative to the axis of thegear without bringing the sides of the rib into binding engagement withthe walls ofthe channels and permitting the gear to function in a normalmanner even though it may have suffered some distortion.

I claim as my invention:

1. A draft gear comprising, in combination, a pair of opposed chamberedfollowers each having longitudinal guide grooves in its top and bottomwalls, a set of friction elements, a central member thereof extendinginto both followers and having top and bottom ribs slidable within theguide grooves, the sides of the endportions of the several ribscooperating withthe grooves of both followers being bowed.

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2. A draft gear comprising, in combina-V tion, a pair of opposedchambered followers each having longitudinal guide grooves in its topand bottom Walls, a set of friction elements, a central member thereofextending into both followers and having top and bottom ribs slidablewithin the guide grooves, both said ribs and grooves having engagingfaces the engaging faces of one of the sev eral interengaging elementsbeing bowed.

In testimony whereof I afiix my signature.

DONALD F. SPROUL.

